Removing this element alone is a really bad decision. By looking at the original map a couple of times it is very easy to use the ring as visual aid and go from there. It is essential for navigation.
In general I think adding more curves does not do any good here. I appreciate people trying to improve the map, and certainly there is much to be improved, but the approach of berlintransitmaps goes in the wrong direction. It is much harder to read than the original map imo.
The biggest problem is contrast.